Excavator



Sept. 4, 1928; 1,682,774.

:5. c. CLUTTER EXCAVATOR Filed March 22, 1927 2 sheets-sheet 1 INVENTOR.E IRE [1E LLJTTER A TT ORNE Y.

Sep t. 4, 1928. 1,682,774

B. C. CLUTTER EXGAVATOR Filed March 22, 1927 2 Sheets-Sheet 2 INVENTOR.Ewen ELILLJTT ER- ATTORNEY.

Patented Sept. 4, 1928.

UNITED STATES 1,682,774 PATENT OFFICE.

BIRD C. GLUTTER, F AKRON, OHIO, ASSIGNOIR, BY MESNE ASSIGNMENTS, 'I'OOLUTTER- WAGNER, INC., A CORPORATION OF OHIO.

' EXCAVATOR.

' Application filed March 22, 1927. Serial No. 177,296.

This invention relates to excavators, and particularly to thoseembodying a dipper arm for carrying the scoop and pivoted on the boom.

In the-operation of such. excavators, es-

pecially whenswinging the 'boom laterally either on'full-revolving orother excavators, inertia forces tend relatively to swing the the dipperand scoop transversely of the l boom which exerts tortional stresses inthe boom structure distorting the same.

The general purpose of the present invention is to provide an improvedpivotalcon nection between the dipper arm and the boom, wherebyrestricted lateral swinging of the arm and scoop will be permitted thusrelieving the boom of heavy tortional strains and also permittingmoreefie'ctive manipulation of the scoop in forming straight or evenunder-cut walls in excavations.

The above andother purposes are attained by the excavator'disclosed inthe accompanying drawings and described below. It is to be understoodthat the invention is not my limited to the specific form thereof shownand described.

.Of the accompanying drawings,

Figure 1 is a part side elevation-"of anexcavator embodying theinvention;

Figure 2 is a section on line 2-2 of Figure 1, and. v

Figure 3 is a detail section of the pivotal mounting for the' dipper armor stick on the boom.

Referring to the drawings, the excavator therein shown isof the ditchertype, such as disclosed in United States Letters Patent No.1,561,694,granted November 17,1925,

but it is understood that many of the bene- Fill its use in any type ofexcavator employing a boom and dipper arm. I

The numeral 10 designates the boom which may be mounted for verticalswinging movement and also for lateral movement in any of the well-knowntypes of full-revolving or lateral swinging boom excavators. Pivoted at11 on the boom 10 is the dipper arm12 carrying a scoop 13 which isactuated by cables 14: and 15, the-former being connected to the arm '12at a point above pivot 11 and the other to the scoop 13 by means of thebale 13 The angularity of the scoop 13 on the arm as herein shown isarranged to M be adjusted automatically by links 16, bellfits of theinvention are tobe derivedfrom in slot's 22, 22 formed through the sidesof a box-bearing 23 secured on dipper arm 12 and having concave,cylindrical bearing surfaces at 24, 24 hearing on bearingmem-" bers 20which preferably have friction material 25 thereon, such as Babbittmetal. The squared extensions'21 cooperating with slots 22 serve to holdthe cooperating hear.

ing members 20 and 23 in proper assembly and also the length of theslots 22 defines the llmlt of relative shifting between bear "mg members23 and bearing members 20.

It will be seen that relative pivotal movement of the arm 12 and boom 10in a vertical plane takes place about pin 11, the whole bearing assembly20, 20 and 23 moving with the arm 12 and capable in any position of'said arm of permitting relative lateral swinging of the arm with respectto the boom which is limited by engagement of extensions 21 with theends of slots 22. This lateral swinging of the arm relative to the boomoccurs when the boom is swung laterally and is the reaction of forcesovercoming the inertia of the stick, scoop and mass of material in thescoop. The lateral pivotal movement ofithe arm is resisted to someextent by the friction .in the bearing and a large measure of the loadpreviously expended in the-boom as tortional stress is absorbed in thearm as longitudinal stress since lateral swinging of the arm elevatesthe center of gravity of the load supported thereby.

In excavating operations it is possible by skillful manipulation of'theexcavator to swing the scoop 13 laterally into such posi-' tions aseffectively to cut square corners and straight or even under cut walls.

Modifications of the invention may be resorted to without departing fromthe spirit thereof or the scope of the appended claim. V

What is claimed is:

An excavator comprising a boom, and a 1m stick pivoted on the boom, thepivot for the on said first bearing member and extensions stick on theboom comprising a pin on the on the first bearing member engaging inslots boom, a bearing member 'journaled on the in the box-bearing memberfor retaining the m pin and formed with transversely curved ,bearingmembers in pro er relationship and 5 bearing surfaces, 9. box-bearingmember limiting relative. latera movement of the i secured to the stickand having surfaees coboom and stick. z operating with said curvedbearing, surfaces BIRD C. CLUTTER.

